It’s sounding like a broken record — literally and figuratively.
For the seventh time in the last ten months, the global land and sea temperatures have established a new record high.
May temperatures were highest ever for land, sea, and land and sea combined.
Furthermore, the temperature for any period of time ending with May is the highest ever recorded for that period.
So much for a slowdown in global warming.
May Temperatures By The Numbers
The following are the reported temperatures and their departures from the 20th century average (all temperatures are in degrees Fahrenheit):
- Combined land and sea: 1.57 above, beating the old record (last year’s) by 0.14.
- Land only: 2.30 above, tying the record set in 2012.
- Sea only: 1.30 above, beating last year’s record by 0.13.
Where Was It Warmest?
It is more instructive to look at the departures from normal in terms of percentiles rather than the absolute number of degrees. Land areas far from oceans have much greater variability than those closer to the moderating effects of the water. The map of May percentiles shows widespread extreme departures from normal, with all-time highs recorded in many locations, including:
- The tropical and southern portions of the Indian Ocean.
- Large parts of tropical and southern Africa.
- Most of northern South America.
- A large swath of the tropical and sub-tropical Pacific Ocean.
- Most of Alaska.
- Peninsular Florida and the adjacent Atlantic waters.
- Much of the Arabian peninsula.
- Part of northern Russia and the waters off Scandinavia.
There were no record cold places in May, but as an indication that global warming is not uniform, there was one much below normal stretch of the North Atlantic Ocean between Greenland and Europe.
Some Highlights Of The May Temperatures:
Here are some highlights of May’s hot temperatures around the world.
- A deadly heat wave in India on the last ten days of the month caused 2,200 fatalities.
- Spain reported its warmest May since 1964.
- Alaska reported its warmest May ever.
- Iceland, Greenland, the United Kingdom, and Norway had cooler than normal May temperatures.
The Breakdown By Hemisphere
The past months have shown significant differences between the hemispheres. The northern hemisphere has much more land area, and thus less moderating effect of water.
This May, the hemispheres were much alike, each warmest ever for sea and combined land and sea temperatures. The southern hemisphere’s land temperature was the second warmest, and the northern hemisphere’s third.
The Period From March To May
The meteorological period of spring in the northern hemisphere and fall in the southern hemisphere was the warmest ever. April was only the fourth warmest, but the record March and May delivered a new March to May record land and sea temperature that was 1.53 degrees above the 20th century average. This beat the old record set in 2010 by 0.04 degrees.
The land and sea separately also set new records for the March to May period.
The January to May period was the warmest on record for all three categories: land; sea; land and sea combined. These records erased the ones set in 2007 and 2010. The latter was an El Niño year, but the El Niño was winding down. The current El Niño, Eggplant, has been getting stronger. There’s no question that 2015 is on pace to be the warmest year in recorded history.
May Sea Ice
The Arctic continued to lose ice, while the Antarctic set new records for maximum ice extent. This conundrum has persisted for several years. The best explanation involves the effect of heating at the poles.
Recent years have featured the jet stream meandering away from the poles due to polar warming, which has outpaced warming elsewhere. In the northern hemisphere, where the pole is mostly water, the effect is to have the ocean heat directly.
In the Antarctic, which is mostly land with water surrounding it at lower latitudes, the northward displacement of the jet stream creates colder conditions where the ice forms.
This is just another indication that global warming can have unexpected results.
Though precipitation varies greatly from month to month, it is important to keep track of anomalies. A trend in precipitation can be more disruptive than a trend in temperature. Ask a Texan.
Some of the May precipitation highlights are as follows:
- Spain recorded its driest May ever.
- Denmark had its second wettest May since record-keeping began.
- The south-central United States set many records for wettest May, and a couple of all-time monthly records.
- Portions of the eastern United States, western Africa, and northern South America were very dry.
May Snow Cover
In North America, May had the sixth lowest snow cover in the 49 years of data. Six of the seven lowest snow covers have occurred in the last six years.
What To Make Of The May Temperature Data?
The monthly upward trend of global air and sea temperature removes the need for any more discussion of whether global warming is occurring.
There are many scenarios that envision a pleasantly livable Earth — and some that don’t. The general circulation of the earth is difficult to model and therefore hard to forecast, but there are some possible futures that look rather dim: Ones with out-of-control greenhouse warming, for example.
UN Climate Conference: What Will Be Done?
An international climate conference will convene in France on November 30. It bears the cumbersome name of the twenty-first yearly session of the Conference of the Parties to the 1992 United Nations Framework Convention on Climate Change and the eleventh session of the Meeting of the Parties to the 1997 Kyoto Protocol. The objective is to achieve a legally binding and universal agreement on climate.
Negotiating such an agreement will make negotiating a curfew with a teenager seem like a piece of cake.
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